Ulcerated tumor on the scalp. Clear-cell hidradenoma

A Study of Histopathologic Spectrum of Nodular Hidradenoma

“…The overlying skin is generally intact, although ulceration with leakage of serous/serosanguinous fluid may be seen. 10 The overlying skin may also be thickened, atrophic, or ulcerated, 11,12 and has a skin-colored, red, or brown color. It is a slow-growing tumor, and rapid growth may represent trauma, hemorrhage, or a malignant change.…”

Nodular Hidradenoma

“…Their average size is 0.5–2 cm, but larger tumors have been reported with a diameter of 9.5 cm 7 . The overlying skin may be smooth, thickened, atrophic, or ulcerated, 8 and has a skin‐colored, red, or brown color 3 . Some tumors may spontaneously drain serous or hemorrhagic material, which may serve as a useful diagnostic sign 9 .…”

Tender Blue Mass in an 8 Year Old

“…The lesions enlarge slowly, and can have a serous discharge (5,6). The superficial skin may be red, blue, brown, or flesh colored (3,7), and signs of erosion or ulceration are frequently apparent (7,8). Pigmented variants have also been described (9).…”

“…The classification and nomenclature of CCH is controversial. The terms apocrine hidradenoma, clear cell myoepithelioma, clear cell adenoma, solid cystic hidradenoma, nodular hidradenoma, eccrine sweat gland adenoma of the clear cell type, and eccrine acrospiroma have been used to describe similar lesions (7,8,18,19). Clear cell hidradenomas are generally considered to be of apocrine origin (8), however, some reports consider them to originate from eccrine glands (1,7,20).…”